Not applicable.
Not applicable.
1. Field of Invention
This invention relates to a one-handed data entry keyboard for use with a computer or like devices. Specifically, the invention describes a keyboard layout ergonomically designed to minimize finger movement based on the most common letters and combinations of letters used in the English language.
2. Related Art
As computers and like devices get smaller and more portable, it is desirable to have smaller than standard-sized keyboards. While the size of the electronics can be reduced to microscopic levels, and the display can be miniaturized and compensated by various methods including scrolling, the keyboard input remains a physical size limitation for the new generation of portable computers. Currently, this need is typically met by the xe2x80x9cminiaturized keyboardxe2x80x9d, in which the size of standard layout keys is reduced to achieve the smaller sizes desired. This miniaturization is typically of a standard QWERTY keyboard, so named for the first six keys on the top row. This approach has limited efficiency and a minimum level of miniaturization, since the size of users"" hands and fingers remains constant. Thus, multiple keys are inadvertently stuck, or the user resorts to typing each key with the forefingers in a xe2x80x9chunt and peckxe2x80x9d style.
A preferred approach to the problem is one-hand keyboards. These keyboards are smaller, since they require fewer keys than the minimum 72-key computer keyboard. By requiring fewer keys, one-hand keyboards can use full-sized keys.
Besides the benefit to miniaturized portable computers, one-hand keyboards are also useful in any application where one-hand use is preferred. Examples of such uses include CAD/CAM operators, who prefer to keep one hand on a xe2x80x9cmousexe2x80x9d input device while the second hand remains on the keyboard; inventory recording devices which allow the user to handle items with one hand while inputting data with the other; and users with disabilities that allow the functional use of only one hand.
One type of one-hand keyboard is a xe2x80x9cchordingxe2x80x9d keyboard. Just as simultaneous striking of keys on a keyboard for a musical instrument, such as a piano, result in a distinct musical chord, simultaneous striking of keys on a chording computer alphanumeric input keyboard result in various letters. These keyboards have a small number of keys, typically five. Thus striking the first two keys may result in the letter xe2x80x9cAxe2x80x9d, and striking the first, third and fifth key may result in the letter xe2x80x9cZxe2x80x9d. These systems have coding systems that are difficult to learn and master. Besides having to learn chording codes for upper and lower case letters as well as numerals, the user must also remember less frequently used commands such as xe2x80x9cControlxe2x80x9d, xe2x80x9cAlternatexe2x80x9d, xe2x80x9cEscapexe2x80x9d, etc.
The preferred one-hand keyboard is of the type described by Tsubai in U.S. Pat. No. 5,793,312, herein incorporated by reference. This keyboard has a plurality of primary alphanumeric keys, at least one secondary key, and a controller. When a primary alphanumeric key is depressed alone, its output signal results in the output of a primary letter, numeral or function. When a primary alphanumeric key is depressed simultaneously with one or more secondary keys, the controller interprets the multiple output signals and outputs a secondary letter, numeral or function. This keyboard operates very well, and is easy to learn the codes that are printed on top of each key as in a standard keyboard. However, a standard for the keyboard layout, based on ergonomic and heuristic principals, needs to be developed for use of such one-hand keyboards.
The speed, pace and rhythm of typing relies in part on xe2x80x9calternating keystrokesxe2x80x9d. It is faster to hit a first key and a second key with different fingers (xe2x80x9calternating keystrokesxe2x80x9d), rather than hitting the same key or different keys with the same finger (xe2x80x9credundant keystrokesxe2x80x9d).
It would be a new and useful improvement of the prior art for a keyboard layout to be developed that is easy to learn and minimizes finger movement and redundant keystrokes.
Accordingly, the objectives of this invention are to provide, inter alia, a new and improved one-hand keyboard layout that:
is easy to learn;
requires minimum finger movement;
minimizes redundant keystrokes;
allows fast data input; and
includes all alphanumeric and functional keys found on a standard computer keyboard.
These objectives are addressed by the structure and use of the inventive one-hand keyboard layout. A nineteen key keypad, comprising fifteen primary and four secondary keys, is laid out in a manner that maximizes the number of character signals generated from located on a xe2x80x9chomexe2x80x9d position or by using single keystrokes. The fifteen primary alphanumeric keys are laid out in three rows with five keys in each row. The most commonly used letters in the English language are on keys in a primary mode (not requiring the simultaneous striking of one or more secondary function keys). Further, the most common two-letter combinations (digraphs) are on keys in the primary mode and proximate to one another. Other objects of the invention will become apparent from time to time throughout the specification hereinafter disclosed.